Star 45

Star 45

Tuesday, September 09, 2008

Fiberglassing notes

From: JFisher
Sent: Tue, 9 Sep 2008 12:03 pm
Subject: RE: [Star45] New Member Introduction

Welcome. In regards to the bunching at the corners, I use a light coat of 3m77 to hold things in place after cutting the folds so they will lay flat. I cut the bottom glass so that it doesn’t wrap the transom, then make a patch that covers the transom and about 1� of the bottom/sides. Same with the bow. I usually do two extra layers of glass at the bow and transom. The glass turns pretty much clear when wetted out so you don’t see the extra glass unless you look really hard. It is slightly thicker and slightly more green. I think have posted a few photos showing the reinforcements. The 3m77 seems to be key to=2 0getting the glass to stay put, but it can discolor the glass is used excessively. It will also move a little when wetted out since the epoxy seems to break down the 77’s adhesive properties.

For the fin/keel, I sand to shape, then wrap with glass (2 or 3 layers of 3 oz on the fin and 1 or 2 layers on the rudder depends how much you sand) that is held in place with 3m77 (light spray or it will show up in the glass.) I then liberally cover with resin, then vac bag with my handy food saver. Vac bagging can be done with commercial peel ply and breather or wax paper and paper towels. Just make sure to poke holes in the wax paper. Sand smooth again, then paint or if going clear I used system 3 clear coat epoxy to build the finish, then sanded again, then clear coat again, then sand, then varnish. I used the clear coat on the hull as well since it fills the minor lumps and bumps without as many coats to paint/sand as varnish.

If think you need practice, I would take a pc of scrap wood and cover it with glass. Cost is minimal and you will quickly learn how the cloth moves when wet. FWIW I like to go a littl e heavy on the resin with wetting out the cloth so it doesn’t want to pull when spreading the resin. I usually use disposable paint brushes to spread the resin and then squeegee it back out with epoxy squeegee’s that I get at the fiberglass store. You want the flexible ones, not the super stiff ones. The one problem with the paint brushes is that they lose bristles, so be ready to pick some off the model while the resin sets.